基于低频信号注入法的PMSM低速无传感器控制

Sensorless Control of Permanent Magnet Synchronous Motors Based on Low Frequency Signal Injection at Low Speed

在永磁同步电机(PMSM)无速度传感器控制方法中通常利用反电动势来估计电机转速,而反电动势在电机低速时会过小,从而导致低速运行时无法实现PMSM的无速度传感器运行,在此采用低频信号注入法实现PMSM低速下的无速度传感器控制运行,通过注入低频电流信号并检测其引起的响应来获取转速信息,实现低速下的转速估计。实验结果证明了该方法正确有效,同时还具有适用性广,对电机参数不敏感的优点。

Back-emf is usually used to estimate motor speed in the permanent magnet synchronous motor（PMSM） sensorless control methods,but the back-emf is too small to estimate motor speed at low speed and sensorless control can not be realized at low speed.The method of injecting low frequency current signal is used to estimate speed at low speed.In this method,the response of the injection current signal is uses to get estimated speed and the control of PMSM speed estimation at low speed can be realized.Experimental results show the feasibility and validity of this method,the method is insensitive to motor parameter and has wide applicability.